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Full-Text Articles in Life Sciences

Influence Of Photosynthetic Photon Flux Density On Uv-Binduced Photoinhibition In Soybean Leaves: Comparison Of Preconditioning And Concomitant Light Treatments, Charles W. Warner May 1982

Influence Of Photosynthetic Photon Flux Density On Uv-Binduced Photoinhibition In Soybean Leaves: Comparison Of Preconditioning And Concomitant Light Treatments, Charles W. Warner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Previous studies indicate that the degree of UV-Binduced photosynthetic inhibition may be highly dependent upon the photosynthetic photon flux density (PPFD, total quantum flux in the waveband 400-700 nm) incident on a plant. This study illustrates that Essex soybean leaves (Glycine max) preconditioned under high PPFD suffered less UV-B-induced photoinhibition than when preconditioned under low PPFD. However, sensitivity to UV-B increased when soybean leaves received high-PPFD as a concomitant treatment.

The relative msgnitude of UV-B-induced damage was similar for both light-limited and light-saturated photosynthesis. This probably indicates that UV-B is inhibiting fundamentally different photosynthetic processes.

Soybean leaves preconditioned …


An Evaluation Of Deschampsia Caespitosa (L.) Beauv Populations For Metal Tolerances And Ecotypic Variation At Climax, Colorado, Paul Ellsworth Pratt May 1982

An Evaluation Of Deschampsia Caespitosa (L.) Beauv Populations For Metal Tolerances And Ecotypic Variation At Climax, Colorado, Paul Ellsworth Pratt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four populations of Deschampsia caespitosa (L.) Beauv (a Poaceae species), growing on disturbed and undisturbed sites at Climax, Colorado, were examined for metal tolerances (Zn, Cu, Pb, Al). Root growth assessments on parent plant and offspring material for each population were conducted using nutrient solutions containing elevated levels of Zn, Cu, Pb, or Al. Seed germination and seedling survival tests for each population were conducted on both alpine topsoil and mine spoil material.

Evidence is presented that supports the hypothesis that ecotypic variation exists within Deschampsia caespitosa and that this variation has allowed certain Deschampsia populations to become successfully established …


Population Characteristics And Movement Patterns Of Cougars In Southern Utah, Thomas P. Hemker May 1982

Population Characteristics And Movement Patterns Of Cougars In Southern Utah, Thomas P. Hemker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Movements of 22 cougars (Felis concolor) were monitored by radio-telemetry between January 1979 and July 1981 in southern Utah. The population, composed of resident, transient, and juvenile cougars, remained relatively constant in size for 3 years. Densities (0.4-0.5 cougars/100 km2) were considerably lower than has been reported elsewhere. Average annual home area size of resident females (685 km2) and a single resident male (826 km2) were substantially larger than other home area sizes reported. Home areas of resident females overlapped and resident male home areas may have overlapped as well. Despite the …


The Isolation And Characterization Of A Novel Iron Protein From Desulfovibrio Gigas, Alan Kay Smith May 1982

The Isolation And Characterization Of A Novel Iron Protein From Desulfovibrio Gigas, Alan Kay Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The isolation, purification, and partial characterization of a novel iron-containing protein from the sulfate-reducing anaerobic bacterium, Desulfovibrio gigas, is described. The highly insoluble protein was isolated from the cell debris following osmotic shock of the bacteria. The insoluble fraction consistently contained about 90% of the cell-associated iron. This protein was treated with acid, chelating agents, detergents and proteases in order to study their effect on the iron solubility. The results of elemental analysis of a crude protein preparation were 5.3% iron, 2.9% sulfur and 11 .9% nitrogen. An independent colorimetric iron analysis showed 6.4% iron. The iron could be …


A Revision Of The North American Species In The Genus Euodynerus (Hymenoptera: Eumenidae), Ali Shallan Moalif May 1982

A Revision Of The North American Species In The Genus Euodynerus (Hymenoptera: Eumenidae), Ali Shallan Moalif

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-eight species of Euodynerus Dalla Torre are recognized from the Nearctic Region, of which one is Holarctic. Literature on the biology of fourteen species is reviewed and new biological information discussed for four species. The phylogenetic relationships of the genus Euodynerus to other genera and the classification and relationships of the species of Euodynerus are discussed. Seven subgenera are recognized of which four are new: Euodynerus, Pareuodynerus Bluethgen, Leucodynerus Bohart, Annodynerus new subgenus, Gonodynerus n. subgenus, Holodynerus n. subgenus and Plecodynerus n. subgenus. Their comparative morphology, phylogeny, and distrubution are discussed. Larval instars of E. hidalgo (Saussure), E. scutellaris …


The Characterization Of Carbamate Resistance In The Colorado Potato Beetle, Leptinotarsa Decemlineata (Say), In Comparison With The House Fly, Musca Domestica (L), Randy L. Rose May 1982

The Characterization Of Carbamate Resistance In The Colorado Potato Beetle, Leptinotarsa Decemlineata (Say), In Comparison With The House Fly, Musca Domestica (L), Randy L. Rose

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Resistant and susceptible populations of the Colorado potato beetle, Leptinotarsa decemlineata (Say), and the house fly, Musca domestica (L), were compared with respect to carbofuran and carbaryl toxicity in the presence and absence of the synergist, piperonyl butoxide. Resistance levels of the New Jersey population when compared with the susceptible Logan population by topical application of carbaryl and carbofuran were > 833 and 820, respectively. A resistance level of 583 was determined from carbofuran bioassays of Rutgers and NAIDM house flies. Similar levels of resistance development between these species suggests the possibility that similar resistance mechanisms may be involved.

Utilization of …


Western White Pine: The Effect Of Clone And Cone Color On Attacks By The Mountain Pine Cone Beetle, Michael J. Jenkins May 1982

Western White Pine: The Effect Of Clone And Cone Color On Attacks By The Mountain Pine Cone Beetle, Michael J. Jenkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relationship between clone and cone color in western white pine, Pinus monticola Douglas, to attack by the mountain pine cone beetle, Conophthorus monticolae Hopkins, was studied in the Sandpoint Seed Orchard, Idaho. A positive relationship was shown to exist during a 5 year field evaluation. Cone beetles were found to prefer dark colored cones and to attack certain clones at a higher rate than others.

Laboratory dissections did not indicate that cone color affected oviposition, brood development or brood mortality.

Olfactometer experiments demonstrated that olfactory stimuli are involved in the cone beetle attack sequence. Visual cues relating to cone …


Muskrat Population Levels And Vegetation Utilization: A Basis For An Index, Thomas R. Mccabe May 1982

Muskrat Population Levels And Vegetation Utilization: A Basis For An Index, Thomas R. Mccabe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Muskrats (Ondatra zibethicus) are associated with marshlands throughout North America. Their impact on marsh vegetation is well documented. In recent years, research pertaining to marsh ecosystems has emphasized the role of interspersion of marsh vegetation to higher faunal diversity and productivity. Muskrats can provide a natural control of aquatic emergents if managed properly. Experimentation at Fish Springs National Wildlife Refuge, Utah, has attempted to ascertain whether vegetation-utilization index could be used for determining muskrat population levels and to evaluate the impact of muskrats on their primary food resource, Olney's bulrush (Scirpus americanus).

Three known populations of …


Effect Of Three Methods Of Processing Barley On Intake And Production Of Lactating Cows, Carlos Garcia Jauregui May 1982

Effect Of Three Methods Of Processing Barley On Intake And Production Of Lactating Cows, Carlos Garcia Jauregui

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-four lactating cows were randomly assigned to three treatments within eight each 3 x 3 latin squares with three periods of 21 days duration. Three processing treatments of barley were 1) steam-rolled, 2) ground (fine), and 3) soak-rolled (soaked in water for appr. 24 hours, rolled, and fed within 48 hours). All rations were fed ad libitum and were comprised of 24% alfalfa hay, 16% corn silage, 35.5% barley, 12% whole cottonseed, 12% wheat bran, 0.3% salt, and 0.3% dicalcium phosphate on a dry matter (DM) basis. Electronic doors were used to collect individual feed intake data. Rations and feces …


A Comparative Study Of Seizure Susceptibility And Serum Calcium, Magnesium And Phosphorus Profiles Of Magnesium Deficient Rats, Nicole H. Bernhard May 1982

A Comparative Study Of Seizure Susceptibility And Serum Calcium, Magnesium And Phosphorus Profiles Of Magnesium Deficient Rats, Nicole H. Bernhard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Magnesium deficiency in rats is known to precipitate audiogenic seizures. An unknown mineral factor in a diet mixture was found to substantially reduce the seizure occurence in magnesium deficient vii animals. This was corrected when the same mineral mixture was remade. Subsequently the faulty mineral mixture was discarded. This research .. as aimed at determining the mineral factor responsible for the observed changes in seizure occurence, and also aimed at investigating the relationships of serum calcium, magnesium and phosphorus concentrations to seizure susceptibility. Treatments to change the serum concentrations of these minerals included dietary manipulation, subcutaneous injection of calcitonin, of …


Assay, Purification, And Characterization Of A Pantetheine Hydrolyzing Enzyme From Pig Kidney, Carl Thomas Wittwer May 1982

Assay, Purification, And Characterization Of A Pantetheine Hydrolyzing Enzyme From Pig Kidney, Carl Thomas Wittwer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A microsomal glycoprotein hydrolyzing pantetheine to pantothenate and cysteamine has been solubilized and purified to homogeneity as determined by sodium dodecylsulfate electrophoresis. Four rapid, independent assays of pantetheine hydrolysis are described and compared along with a method for localizing enzymatic activity on polyacrylamide gels. The enzyme is solubilized on exposure to butanol and purified by heat treatment, (NH4)2SO4 fractionation, hydrophobic chromatography, and hydroxyapatite chromatography. The glycoprotein, purified 5600-fold in 22% yield, has a specific activity of 14 μmoles pantothenate produced/min/mg of protein, 35 times that previously reported. The enzyme has a pH optimum of 9.0-9.5 and a …


The Interactive Effects Of Water Salinity And Management On Symbiotic Nitrogen Fixation In Alfalfa, Thomas J. Keck May 1982

The Interactive Effects Of Water Salinity And Management On Symbiotic Nitrogen Fixation In Alfalfa, Thomas J. Keck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A greenhouse study was conducted to assess the interactive effects of three irrigation water salinity levels (1.0, 3.0, and 9.0 mmho/cm) and three quantities of water app lied per irrigation (120, 240, 360 ml) on plant growth and nitrogen fixation by alfalfa (Medicago sativa L. cv. Resistador). Harvest dates corresponded to 10, 30, and 50 days after the initiation of salt and water treatments which were started after nodulation had been established in young plants.

Alfalfa top growth was limited by both salt and water stresses. Irrigation water salinity had a greater effect on top growth than root growth …


Scanning Electron Microscopic (Sem) Studies On Range Grasses And Their Resistance To Black Grass Bugs, Yun-Hwa Ling May 1982

Scanning Electron Microscopic (Sem) Studies On Range Grasses And Their Resistance To Black Grass Bugs, Yun-Hwa Ling

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Large populations of black grass bugs, Labops hesperius Uhler, have been observed on extensive acreages of range lands. These bugs cause severe damage to the range grasses, lowering their palatability and productivity. This study was to determine whether morphological differences among breeding lines of grass species or interspecific hybrids could be correlated with the feeding behavior of black grass bugs. If so, plant breeders should be able to develop resistant cultivars. To explore this possibility, cultivars and synthetics of range grasses, representing the genera, Agropyron, Dactylis, Phalaris and Poa, were exposed to different instar stages (II and …


Evaluation Of Allergic Hypersensitivity To 2,4-D, Malathion, And Captafol In Mice, Janette R. Cushman May 1982

Evaluation Of Allergic Hypersensitivity To 2,4-D, Malathion, And Captafol In Mice, Janette R. Cushman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

2,4-D-specific IgE antibodies were detected in serum of BALB/c mice using the rat passive cutaneous anaphylaxis (PCA) test following the second intraperitoneal immunization with 1, 10, or 100 ug of 2,4-D0keyhole limpet hemocyanin (KLH) conjugate administered with aluminum hydroxide adjuvant. The groups that received 1 ug of 2,4-D conjugate had the highest antibody titers (geometric mean of 60). A paper radioallergosorbent test (PRAST) was developed for determination of 2,4-D-specific IgE. The PRAST was equally as sensitive as and showed a positive correlation with the PCA assay.

The anhydride of the diacid metabolite of malathion (MMA) coupled to KLH elicited MMA-specific …


The Effect Of Rain Leaching On Field Dried Alfalfa Hay Yield And Lamb Production From The Hay, John M. Kaykay May 1982

The Effect Of Rain Leaching On Field Dried Alfalfa Hay Yield And Lamb Production From The Hay, John M. Kaykay

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A 2 x 3 x 2 factorial arranged split plot experiment was used to determine the decrease of dry matter yield from field-dried alfalfa hay caused by the application of a measured quantity of artificial rain (sprinkling irrigation). The three hay treatment factors were (1) alfalfa hay was cut at late vegetative and early bloom stage of maturity and (2) leached by 0, 5 mm or 20 mm of artificial rain applied by sprinkling and (3) sprinkled in the swath, 24 or 48 hours after cutting.

Changes in dry matter yield were not significantly (P < .05) related to stage of maturity of forage, level of artificial rain applied or the time of application of artificial rain. There were no significant interactions for dry matter yield. The non-significant results were probably due to the variability of the alfalfa stand among the specific areas harvested for each treatment and insufficient replications to control the variability.

Forty-eight lambs were fed for …


Cougar Predation And Ecological Energetics In Southern Utah, Bruce Bennet Ackerman May 1982

Cougar Predation And Ecological Energetics In Southern Utah, Bruce Bennet Ackerman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diet of cougars (Felis concolor) was studied from December 1978 to August 1981, on a 4500 km2 study area near Escalante, Utah. Prey eaten was determined from analysis of 112 animals consumed as prey, and from 239 cougar scats. Mule deer (Odocoileus hemionus) were the major prey item, comprising 81% of biomass consumed. Lagomorphs, large rodents, and smaller predators were also important components. Cattle comprised <1% of the diet, although commonly grazed on the cougar's summer range. Adult male and juvenile (<1yr) mule deer were killed more often than expected, in fall (P<0.10) and in winter (P<0.005). Cougars were a major cause of mortality of adult deer (41% of all adult female deaths, 35% of male), but only 6% of mortality of juveniles. Selection of prey seemed to be a function of prey vulnerability, rather than one of active choice by the predator.

Motion-sensitive radio-transmitters were placed on 15 cougars, from 3 months to 7-9 years of age. Three parameters of the radio signal were used to determine activity levels during 6843 …


The Influence Of Winter Social Behavior On The Habitat Selection And Reproductive Success Of The Black-Billed Magpie, Kerry P. Reese May 1982

The Influence Of Winter Social Behavior On The Habitat Selection And Reproductive Success Of The Black-Billed Magpie, Kerry P. Reese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the influence of winter social behavior, particularly dominance relationships, on the subsequent nesting habitat selection and reproductive success of Black-billed Magpies (Pica pica hudsonia) on 2 areas in northern Utah. Hierarchical cluster analysis ordinated the habitats available to breeding birds and Chi-square and Bonferoni-z statistics were used to determine those habitat types the magpies seemed to prefer. Social status was determined by observing color-banded birds engaged in agonistic encounters at winter bait stations. Social dominance was evaluated by % dyads won, not by total % victories. Relationships between winter social status of magpies and their …


Reproductive Behavioral And Physiological Traits In Domestic, Wild, And Hybrid Ovis, Kara-Lynn Crocker-Bedford May 1982

Reproductive Behavioral And Physiological Traits In Domestic, Wild, And Hybrid Ovis, Kara-Lynn Crocker-Bedford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was part of a program to develop new genotypes of sheep (Ovis spp.) and goats (Capra spp.) which are more useful for food and fiber production. The study examined the influence of domestication on behavioral and physiological traits of ewes and lambs, the influence of a single or twin offspring on ewe and lamb behaviors, and general relationships between ewes and lambs during the lambs' first month of life.

Domestication has caused the intensities of observed traits to diverge greatly from the tendencies shown by wild populations. Domestication has produced increases in measurements associated with maternal …


Efficacy Of Denning In Alleviating Coyote Depredations Upon Domestic Sheep, James A. Till May 1982

Efficacy Of Denning In Alleviating Coyote Depredations Upon Domestic Sheep, James A. Till

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bands of domestic sheep lambing on the open range in south central Wyoming were monitored for predator losses prior to and following coyote (Canis latrans) removals. Experimental treatments, including 1) no removal (control), 2) removal of 2 adults and their pups, and 3) removal of pups only, were replicated 15 times each. Number of predation incidents (events) was reduced 98.2% by removing adults and pups. The number of sheep killed was reduced by 98.8%. Removing only litters of pups resulted in a decrease of 87.7% total kills decreased 91.6%. in predation incidents, while Overall, 23 of 30 predation …


The Relative Roles Of Initial And Residual Sodium Nitrite On Germination Of Clostridium Botulinum Spores In Meat, Orchid Mettanant May 1982

The Relative Roles Of Initial And Residual Sodium Nitrite On Germination Of Clostridium Botulinum Spores In Meat, Orchid Mettanant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four levels of NaNO2 (0 ppm, 50 ppm, 100 ppm, and 156 ppm) were tested for antibotulinal activity in ground pork inoculated with spores of Clostridium botulinum either at the time of formulation or after cooking. Samples formulated with less than 156 ppm sodium nitrite received additional nitrite to adjust the residual nitrite equal to that found after cooking in samples formulated with 156 ppm nitrite. All samples were subjected to abusive storage at 27 C. Inoculating the spores at the time of formulation resulted in a faster rate of swelling. Heating C. botulinum spores for 30 min. at …


Use And Evaluation Of The Nutrient Density Concept For Assessing The Impact Of Socioeconomic Factors On Nutritional Quality Of Diets, Carol Thompson Windham May 1982

Use And Evaluation Of The Nutrient Density Concept For Assessing The Impact Of Socioeconomic Factors On Nutritional Quality Of Diets, Carol Thompson Windham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Data from 7285 individual participants in the USDA Spring Nationwide Food Consumption Survey were analyzed using the nutrient density concept and multiple regression procedures to evaluate the impact of socioeconomic status on the nutritional quality of foods consumed. For each socioeconomic group the average daily amount of nutrients consumed per 1000 kcal of food consumed were computed and compared with the Recommended Dietary Allowances which had been converted to single-value nutrient allowances per 1000 kcal. This nutrient density approach identified qualitative patterns of food consumption for selected income, region, urbanization, household size, race, employment and education groups as well as …


A Nutrition Education Componenet For Migrant Children Based On The K-6 Nutrient-Density Curriculum, Sandra Beadleson May 1982

A Nutrition Education Componenet For Migrant Children Based On The K-6 Nutrient-Density Curriculum, Sandra Beadleson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A nutrition education component was developed, implemented, and evaluated for integration into the Title I migrant education program. The component was based on an evaluated nutrition education curriculum implemented by Brown in the elementary school. The nutrition education program was developed on the concept of nutrient density which measures the ratio of a food's nutrient contribution to its caloric contribution on a constant caloric basis. The nutrition component was modified to include behavioral objectives and concepts that partially met the needs of a migrant population in Utah.

The program was evaluated in the Title I programs in Corrine and Smithfield, …


Estimating Esterase And Monooxygenase Detoxication By Bioassay, Electrophoresis And Metabolic Studies In Pea Aphid, Acrythosiphon Pisum (Harris) Populations (Homoptera: Aphididae), Deifalla H. Al-Rajhi May 1982

Estimating Esterase And Monooxygenase Detoxication By Bioassay, Electrophoresis And Metabolic Studies In Pea Aphid, Acrythosiphon Pisum (Harris) Populations (Homoptera: Aphididae), Deifalla H. Al-Rajhi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The role of esterases and monooxygenase in the detoxication vii processes of field populations of pea aphids was studied in relation to seasonal changes, developmental stage, and treatment with DEF and piperonyl butoxide. LCSO values for 12 hour exposure periods in glass vials ra nged from 0.04-2.3 micrograms / vial and 820-4871 J.Jg/vial for paraoxon and carbaryl, respectively. Topical bioassays showed the adults to be more tolerant to paraoxon (LDSO of 1. 4-12.3 ng/aphid) toxicity than nymphs (LDSO of 0.13-4. 7 ng/aphid).

Treatment with DEF® (S,S.S-tributylphosphorotrithioate) enhanced paraoxon toxicity against the pea aphid whereas piperonyl butoxide had little …


Endocrine And Physiological Responses Of The Female Goat During Three Reproductive Phases, Dana Dean Clark May 1982

Endocrine And Physiological Responses Of The Female Goat During Three Reproductive Phases, Dana Dean Clark

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Female Spanish x Dairy cross goats were divided into three reproductive phases--breeding season or cyclic (20), seasonal anestrus (20), and early postpartum (20). Each group of animals was further divided into three treatments--control (10), Gonadotropin Releasing Hormone (GnRH) treated (5), and pituitary Luteinizing Hormone (LH) (5). During each of the above mentioned reproductive phases, the following were measured: progesterone and LH profiles, serum LH levels following GnRH injection, pituitary LH concentration and ovarian responses following GnRH treatment.

Progesterone levels indicative of luteal development were present only in the breeding season. Progesterone levels during the seasonal anestrous and postpartum periods were …


Nutrient Requirements Of Ruminants In Developing Countries, Leonard C. Kearl May 1982

Nutrient Requirements Of Ruminants In Developing Countries, Leonard C. Kearl

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This book was assembled using the latest information for compiling the nutrient requirements of sheep, goats, cattle and water buffalo. Because of the complexity of the interactions between an animal, its diet, its physiological state, and the environment; the values depicting the nutrient requirements are estimates and not absolutes. These values, however, are considered to be adequate to meet the minimum requirements of healthy animals maintained in a thermoneutral environment.

The mean energy and protein values used in the nutrient tables were arrived at from combining values found in the literature and those provided in personal communication with animal nutritionists …


Plant Spacing: A Size Sensitive Model With Implications For Competition, Robert L. Bayn Jr. May 1982

Plant Spacing: A Size Sensitive Model With Implications For Competition, Robert L. Bayn Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An algorithm is presented which partitions space among mapped plants according to their relative sizes and positions using one of eight rules for locating boundaries between individuals. The performance of those rules is examined using several natural and artificial data sets with diverse measures of individual size. The relative performance of the rules was the same for all natural data sets examined. The best rule, as measured by a high correlation between individual size and assigned space, placed the boundary at a distance between neighbors proportional to the relative sizes of neighbors as long as a maximum distance (also a …


A Study Of Cell Dimensions, Amyloplast Position And Certain Physiological Responses During Gravitropic Bending Of Dicot Stems, Julianne E. Sliwinski May 1982

A Study Of Cell Dimensions, Amyloplast Position And Certain Physiological Responses During Gravitropic Bending Of Dicot Stems, Julianne E. Sliwinski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

If a plant is positioned horizontally, the elongating region responds by bending upward within 10 to 12 h until it is vertical, forming a 90 bend with the stem below. If a Xanthium strumarium L. (cocklebur) plant is placed horizontally, but restricted to that position for 48 h and then released, the bend to the vertical usually takes place within 10 s, suggesting that bending energy is stored in restricted stems. Some plants that do not bend completely to 90° within 10 s do so within 5 min, and other plants can overshoot the 90 mark by as much …


Influence Of Phosphorus And Water Management On Mycorrhiza And Rhizobia In Symbiosis With Legumes, David C. Ianson May 1982

Influence Of Phosphorus And Water Management On Mycorrhiza And Rhizobia In Symbiosis With Legumes, David C. Ianson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mycorrhizal associations are very important to plant growth. This is mainly due to the hyphal stands that are able to utilize concentrations of nutrients that would normally be considered unavailable for plant growth, especially phosphorus. These associations are of great importance in soils that have been disturbed by mineral extraction and are consequently low in available nutrients. The ability of mycorrhizal fungi to form associations on disturbed sites may be dictated by a number of factors: moisture, soil pH, soil fertility (including heavy metal ions), salinity, and plant response.

Two factorial experiments were conducted with the legume Hedysarum boreale cv …


Seed Case Studies On Atriplex Gardneri (Moq) Dietr.: Bracteole Cell Wall Composition And Enzymatic Degradation, Priscilla Woolley Burton May 1982

Seed Case Studies On Atriplex Gardneri (Moq) Dietr.: Bracteole Cell Wall Composition And Enzymatic Degradation, Priscilla Woolley Burton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Clarification of the bracteole restraint on germination and the development of an improved seed pre-treatment were the objectives of this study. Bracteole cell walls were isolated and hydrolyzed with 72% sulfuric acid followed by dilution and further hydrolysis. Individual monosaccharide yields were monitored with gas chromaixtography and colorimetry. Lignin was determined as the acid insoluble residue . Cell wall composition on a dry weight basis was 17.0% lignin, 32 . 75% glucose, 28.77% xylose, 7.21% arabinose, 1.11% galactose and 0.35% mannose. Linear xylans and glucans represent a large portion of the cell wall . The quantity of lignified tissue is …


Pharmacokinetic Assessment Of The Influence Of Dietary Fiber On The Absorption And Disposition Of Selected Model Xenobiotics As It Relates To Colon Cancer, Joseph Donald Debethizy May 1982

Pharmacokinetic Assessment Of The Influence Of Dietary Fiber On The Absorption And Disposition Of Selected Model Xenobiotics As It Relates To Colon Cancer, Joseph Donald Debethizy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Selected drugs are being utilized as models of putative colon carcinogens in a study of the influence of major types of dietary fiber upon drug pharmacokinetics. Adult, male Wistar rats were pretreated with standardized, isocaloric hydrated gelatin diets containing no fiber or 15% (w/w) cellulose, lignin, hemicellulose (metamucil), or pectin for 30 days. An additional group was fed lab chow ad libitum as a reference control.

The pharmacokinetics of acetaminophen, FD & C Red No. 2 and mirex were examined following oral administration in three separate experiments. Among fiber types, pectin and hemicellulose (Metamucil) caused higher peak plasma concentrations of …